Textile operations often require simultaneous handling of many continuous linear elements, such as yarns or strands. An example of one such operation is the production of rovings by winding together multiple strands of fibrous material such as glass fibers. The quality of the roving is dependent upon winding together a set number of strands to produce a particular roving product.
It has been a practice to produce a composite roving by withdrawing strands of glass fibers from packages held in creels and converging them into a group or roving and winding the roving onto a rotatable packaging tube, collet or collector. It has been found that one of the major problems in producing such a composite linear roving product lies in maintaining a set number of strands being wound into the roving package.
This problem was recognized by Patterson, U.S. Pat. No. 4,010,908, wherein he used discrete logic devices, specifically, NAND gates and a decoder to produce a control signal which would stop the winding process if the number of strands being wound falls below an acceptable level. Patterson, although an advancement at its time, does not allow communication of any information to supervisory digital computers which control other processes or log the history on products being produced. Changing to another roving product requiring a different number of strands also proved difficult using the apparatus disclosed by Patterson.
Rapp and Zolnerovich, U.S. Pat. No. 4,344,582, recognizing the shortcomings of Patterson, developed a microprocessor-based system for controlling the entire roving process. The system described by Rapp et al included strand detection, automatic strand insertion, winder motor speed control, motor acceleration control, mandrel or collet control and included in memory a library of product codes with number of strands to be wound for a given product. The Rapp et al system is an excellent system, but it is expensive to build and install. What is needed is a low cost microprocessor system which has the limited control features of Patterson but which can also communicate information to a supervisory host computer which is currently controlling other functions such as strand insertion, motor speed, motor acceleration and doff controls.